Devices exist in the prior art for locating the depth of a bed of a body of water and for setting the hook at any preferred distance above such bed, e.g. see U.S. Pat. Nos. 2,208,240; 2,984,040; 3,057,107 and 3,381,407. However, such devices suffer from numerous disadvantages such as complexity and number of internal parts, parts which readily deteriorate, failure of mechanisms contained therein to positively lock the line in a desired position, difficulty in threading the line through the device, etc.
The present invention overcomes all of the disadvantages associated with the prior art devices. Indeed, the present device utilizes, as the disengagement means (to be described in detail below) the mechanism associated with the common ball point pen. That is, in the ball point pen, when the top plunger is held down (by finger pressure), the pen tip is fully extended; this is referred to as position "A", which is analogous to that described in detail in FIG. 1. below.
When pressure is released on the plunger, the pen tip is retracted slightly into the writing position; this is referred to as position "B", which is analogous to that described in detail in FIG. 2 below. Of course, the pen tip could be in a fully retracted position upon release of the plunger if the position prior to depression of the plunger was position B.
When the plunger is again fully depressed, position A is present and when pressure on the plunger is released the pen tip will be fully retracted in the pen barrel -- this is referred to as position "C", which is analogous to that described in detail in FIG. 3 below.
Thus the action of the common ball point pen is position A -- position B -- position A -- position C -- position A - - - etc. Analogously, the device of this present invention will undergo the actions: FIG. 1 -- FIG. 2 -- FIG. 1 -- FIG. 3 -- FIG. 1 - - - etc.
The disengagement means may be any mechanism which is known in the art as being useful for protraction and retraction, especially protraction-retraction mechanisms for tubular members such as ball point pens. Such disengagement means are conventional and do not form part of this invention. However, the protraction-retraction mechanism described in U.S. Pat. No. 2,905,147 issued Sept. 22, 1959 to Frank T. Johmann and entitled "Protraction-Retraction Mechanism For Writing Instruments" is especially useful for this invention and is herein incorporated by reference.